American Agricultural Area (1847-1940) The Gold Rush and the annexation of California by the United States brought drastic changes to San Pablo. A stage route was established from San Francisco and Oakland to Sacramento, and ran right along the road we call San Pablo Avenue today. A small stage stop village began to appear around the Castro/Alvarado Adobe home at the corner of San Pablo Avenue and Church Lane.
Saloons lined the main street, which was wide enough (60~100 feet) to accommodate the movement of cattle herds. The Castro descendants began to sell off portions of their Rancho to American ranchers and farmers. A Post Office was established, a school was built, and churches founded.
Many of the new ranchers were new immigrants to the United States, and most of them were Azore Island Portuguese. There were also immigrants from Chile, Germany, France, and China. A large camp of Chinese shrimp fishers lived along the edge of San Pablo Bay from 1870 to 1912. (San Pablo went all the way to the bay in those days.) A few African-Americans lived in the area as well. We can assume that a number of Mexicans, such as the Castros and Alvarados, continued to live here also.